diff --git a/arch/sim/src/up_releasestack.c b/arch/sim/src/up_releasestack.c
index 248f6b712c2..49a68eb8d79 100644
--- a/arch/sim/src/up_releasestack.c
+++ b/arch/sim/src/up_releasestack.c
@@ -40,7 +40,9 @@
 #include <nuttx/config.h>
 
 #include <stdlib.h>
+
 #include <nuttx/arch.h>
+#include <nuttx/kmalloc.h>
 
 #include "up_internal.h"